Smelting-furnace.



No. 757,221. PATENTBD APR. 12, 1904.

' A. R. PARTRIDGE. SMBLTING FURNACE.

APPLIOATIOH FILED MAR. 30, 1900. RENEWED JULY 22, 1903.

N0 MODEL.

ratenteaja rn 12, 1904.

- U TED STATES PATENT ()FFICE.

ALLEN R. PARrRIDGE, OF sAN FRANCISCO, CALIF RNIA, ASSIGNOR or ONE-HALF TO FRANK W. PAGE, OF sAN rnANorsoo, CALIFORNIA.

S MELTING-FURNACE.

SPECIFICATION forming part of Letters Patent No. 757,221., dated April 12, 1904. Application filed March 30, 1900.- Renewed July 22, 1903. Serial No. 166,636. (No model.)

To all whom it may concern:

, Be it known that I, ALLEN R. PARTRIDGE, a citizen of theUnited States, residing at San Francisco, in the county of San Francisco and State of California, have invented certain new and useful Improvements in Smelting-Furnaces, of which the following is a specification. My invention relates to the treatment of ores for extracting metallic matters, bullion,

&c., and refers particularly to an improved construction of smelter. p

This smelter isespecially adapted to carry out the process of treating ore described in'an application for Letters Patent filed upon the sane date as' the present case and numbered 10, 59.

The invention is fully hereinafter described, 1 and is shown in the accompanying drawings, in which Figure 1 is a side elevationof the smelter,

broken away in parts to show vertical sections.

Fig. 2 is a plan view. Fig. 3 is a plan of the portable hearth.

A represents a stack, preferably circular in section andsupported in any suitable way, as

.by the angle-brackets a and beams b, thellatter forming part of some suitable supporting.

structure. The stack may be constructed of iron and wateracketed, as shown at a. or can be built of brick or maso ry, if preferred.

It is entirely open at the b0 tom.

B is the charging-door, which I prefer to place atthe top, asshown, although this is not essential. y

D is an outlet-pipe for the products of combustion, which leads from the side of the fur.- nace near-the top. If provision ismade for charging the furnace from the side, however, the escape may be through the top of the stack. I have illustrated the preferred construction.

Holes 10 p are provided at intervals around the furnace, which may be opened for the purposes of inspecting and of stirring the charge.

P is a water-feed pipe to the jacket, and O is the jacket outlet-pipe.

Beneath this open-bottomed furnacestructure is a hearth C, separated from the furnace, so as to form an open space, which is the draft inlet and which extends entirely around. This hearth is preferably a circular I casing 0, having an interior refractory lining and bottom 0. At one side, near the top, is a slag-spout 0Z, while near the bottom and opposite is another spout, e, for tapping the matte, bullion, or other product, The hearth is provided with a drop-bottom c c for obtaining access to the bottom and lining from below. The upper edge of the hearth cooperates with theloweredge of the furnace to provide the open draftspace referred to, and in "order to control the draft and to regulate the quantity of air admitted I make the said upper edge adjustable toward and from the furnace. This can be done in the manner shownby bodily moving the entire hearth toward or away from the furnace, as by the screws f, provided with handwheels f and which engage with threads formed in the base of the hearth and bear upon some solid support beneath. It

.will be observed by reference to the drawings that these screws are independentlymovable, so that the hearth may be raised equally on all sides or may be inclined'by raising one part more and another less. The purpose of. this 'i'sto-increase or diminish the draft upon one side or the other, as the contents and conditions of the hearth may require.

Inaddition to a vertical adjustment for controlling the-draft-space I find it good and economical practice to make the hearth'portableand entirely removable from below the stack, so. as tobe interchangeable with one or more others of like construction. In this manner I save time and expense in case repairs are needed to a hearth by substituting another. By having the hearth movable I also save time and expense whenever it becomes necessary to blow the furnace in or out in case of the freezing Qf a charge or the formation of sows or accretions, which are det rimental to the success of the smelting operation. A track 9 islaid across the pit, upon which run carrying-wheels c, by which the hearth is portably supported- The screws f pass through the brackets f and can bear upon the trackvrails or at one side, as shown in- Fig; 3, upon any suitable solid part of the track structure. Between the open-bottomed stack and the open-topped hearth a continuous draft-space thus exists, controllable as to size and adapted to admit a flow ofair uni formly'throughout its extent. I attach great importance to this manner of admitting a continuous and undivided volume of air to heat from the zone before reaching the latter,

and this radiation takes place uniformly throughout the extent of the air-flow, since there are no cross-currents, but only a uniform flow. Thus without previous heating and without expensive mechanical forcing devices I produce a hotter and more effective zone at a considerable reduction in expense.

The necessary draft is produced in my fur nace by exhaust or suction operating to-produce a vacuum inthe stack, and I do this by means of a steam-in ector operating in connection with an outlet from the stack for products of combustion. Near the upper end of the structure is the escape-pipe D, which communicates with a flue E, which may extend vertically or at any angle, provided that it extends across the end of the pipe D. Within the flue E and near its end its inner diameter is reduced bya plug 0, which forms an injector-nozzle. A pipe F enters steam-tight through the closed end of flue E, through which steam from any suitable boiler is supplied ,and injected through the plug. The steam passes the outlet from the smelter and fills the flue beyond it, and it must always be liberated so as to pass such outlet. The result is that the flue is filled with rapidly-escaping steam, which continues on past the furnace connection and in the flue beyond, thereby excluding air from the flue and drawing gases, &c., from the interior of the stack in'the manner of a piston. From the flue the steam passes into the stack, which is larger than the flue, and these successive enlargements of the steam-passage. prevent any back pressure. The injector tends to produce a vacuum in the stack, which of course causes a strong inflow of air from below in the manner already described. I may mention here that air under pressure may be used as an injector for creat ing a vacuum in the stack and producing the draft, and although in such case I should be put to the expense of air-forcing devices I should still obtain an economical advantage over the use of such devices for producing the draft by direct pressure from below. This will-be understood byreference to the previous description of the character of the draft inmy smelter, which cannot be produced by direct pressure, but can be produced by any effective means for causing a vacuum in the stack. The flue E may openinto the air or may lead to a condensing and'dust-precipitating chamber, where fumes and dust carried by the steam are condensed and precipitated.

It is essential to my invention and the successful operation .of the furnace that the junction of the escape-pipe with the flue shall be at a point intermediate between the contracted part in which the injector is located and the discharge end of the flue, so that the blast of steam or air shall impinge against the products of combustion as they emerge from the pipe into the flue.

When the furnace is charged at the top, as shown,the escape-pipe D and flue E are practically continuations of the stack, and they are shown in the manner in which I prefer to arrange them. In some cases, however, as in smelters for copper, where it is not desired to use a precipitation-chamber, the products of combustion can escape through an open-topped stack bnd the air orv steam pipe can be led into the furnace at a point where the stack is contracted to produce the injector effect and the consequent vacuum below.

I do not limit myself to the specific details of construction herein described and shown in the drawings, as I desire to avail myself of such modifications and equivalents as fall properly within the spirit of my invention as herein set forth and claimed.

Having thus fullydescribed my invention, what I claim-as new, and desire to secure by Letters Patent, is

1. In a smelter, an outlet for products of combustion, a flue having'one closed end and extending across and communicating with said outlet and of reduced diameter at one side of said outlet, and an injector-pipe placed at said closed end in the reduced part thereof, and discharging in said contracted part between the closed end and the outlet whereby the fluid injected through said pipe will be discharged past said outlet and fill the normal area of the flue beyond the outlet.

' 2. In a smelter, an outlet for products of combustion, a flue having one closed end and extending across and communicating with said outlet, and of reduced diameter at one side of said outlet, an injector-pipe entering through said closed end and into the reduced diameter;

and a stack of greater diameter than the normal diameter of the flue, and communicating therewith, whereby a fluid injected through said pipe will be discharged past the said outlet, will fill the normal area of the flue beyond 

